Brake equipment



sept- 17, 1940 E. E. HEwl'rT 2,215,354

` BRAKE EQUIPMENT Filed Feb. l, 1956 2 Sheets-Sheet l @am n@ sept. v17,1940.

E. E.,H|.:w|TT 2,215,354

BRAKE EQUIPMENT Filed Feb. 1, 1956 2 sheets-sheet 2 APPL/CAT/o/v Tl .3.

A FrEL EASE HANDLE-UFF RELEASE Yi Eig@ L AP 37 SERV/C\)// /8 /76@ELE/45E H/-vvDEE-Q/:F HANDL Oni F 9 V46 /6/ A 6 5 PPL/cAT/o/v I l h 4/60 INVENTOR 58 64 ELLIS E HEWITT RELEASE HANDLE @EE BY ATTORNEYPatented Sept. 17, 1940 UNITED STATES 2,215,354 BRAKE EQUIPMENT f EllisE. Hewitt, Edgewood, Pa., assignor to The Westinghouse Air BrakeCompany, Wilmerding, Pa., a corporation of Pennsylvania ApplicationFebruary 1, 1936, SerialNo. 61,964

34 Claims.

This invention relates to brake equipments, and more particularly tobrake equipments for high speed trains and traction vehicles.

Brake equipments have heretofore been pro- .i posed for high speedtrains and traction vehicles in which three types of brakes have beenemployed, namely, a fluid pressure brake, a magnetic track brake, and adynamic brake. The

` dynamic brakes comprise the vehicle driving l0. motors and suitablecontrol mechanism for connecting the motors in a dynamic braking circuitwhen it is desired to decelerate the train or vehicle.

In these proposed equipments the magnetic track brakes and dynamicbrakes. only are applied when making normal stops, with the fluidpressure brakes being cut into action near the end of the stop, at whichtime the effectiveness of the dynamic brakes decreases. When the trainthus cornes to rest, the magnetic track brakes and the fluid pressurebrakes will be applied while the dynamic brakes will be Wholly.

ineffective.

If the magnetic track brake windings should remain energized for verylong after the train or vehicle comes to rest, there is danger ofburning out these windings due to overheating. The magnetic track brakewindings should therefore be deenergized at the time the vehicle ortrain comes to rest, or shortly thereafter.

Since the reason the magnetic track brakes are to be cut out at the endof the stop is due to the danger of overheating and burning out of thewindings of these brakes, it is preferable that the means which isemployed to cut the brakes out of action be responsive to thetemperature of these windings, or a temperature proportional thereto.

It is a general object of the present invention to provide a brakeequipment employing fluid pressure brakes, magnetic track brakes, anddynamic brakes, in which the dynamic and track brakes are employed tomake normal stops, with the fluid pressure brakes automatically cut intoaction at or near the end of the stop, at which time the dynamic brakesdecrease in effectiveness, and the magnetic track brakes cut out ofaction when the temperature of their windings reaches a predeterminedvalue below the danger 5o point.

Where such a plurality of brakes are employed it is desirable that thecontrol thereof be embodied in a common mechanism which may be manuallycontrolled with great facility. If such a common control were to bedirectly coupled (Cl. 30S- 3) to and operated by a control handle, suchas that commonly employed in uid pressure brake systems alone, themanual effort required would be so great as to render the controlinexible. Another object of the present invention is to pro- 5. vide amanual control which requires only a light manual force `to operate,thereby providing a high degree of flexibility. K y

A yet further object of the vention is to provide a .brake equipmentemploying the three 10 types of brakes hereinbefore referred to, inwhich thermal means are employed to cut the magnetic track brakes out ofaction when a predef termined temperature, corresponding `to thatproduced in the track brake windings, is attained. 15

A still further object of the invention is toprovide a brake equipmentofthe type hereinbefore referred to in which applications of at leastone of the brakes employed may be effected from the rear end of thevehicle or train when backing up. 20 y Fig. 1 is a diagrammatic andschematic View 25 of one embodiment of the invention adapted for asingle vehicle,

Fig. 2 shows the various positions for the handle in the main brakecontroller shown in Fig. 1,

Figs. 3, 4 and 5 show in fragmentary form de- 30 tails of portions ofthe main brake controller shown in Fig. 1,

Fig. 6 is a diagrammatic view of the brake valve device for the fluidpressure brakes shown to the lower right in Fig. 1,

Fig. 7 shows in diagrammatic form the communications` established in thederail throwing brake valve, shown to the upper left in Fig. 1, whenthis brake valve isin application position,

Figs. 8, 9 and 10 are detail views of the backing 40 up brake valveshown to the upper right in Fig. 1.

Considering now briefly at first the embodiment shown in Fig. 1, thefluid pressure brakes are represented by the brake cylinder I0, themagnetic track brakes by the `magnetic track 45 brake device II, and thedynamic brakes by the' vehicle driving motors which have armatures I2and field windings I3. l f

The fluid pressure brake system may comprise a control valve device I4,two double check valve devices. I5 and I6, a derail throwing brake valvedevice Il, a backing up brake valve device I8, a check valve device I9,and a main reservoir 20.

The magnetic track brake system may comprise a raising cylinder 2l, amagnet valve device 55 22, a thermal relay 23, and an electrical relay25.

The dynamic brake system may comprise the vehicle motors heretoforereferred to, and a power controller 24, which is employed to supplycurrent to the driving motors when driving the vehicle. Both the dynamicbrakes and magnetic track brakes may be controlled from a commoncontroller device indicated at 26.

A master control mechanism, for controlling applications of all of thevarious brake systems above referred to, is shown at 28.

In order that the fluid pressure brakes shall be suppressed when thedynamic brakes are effective, there is provided a relay 30 connected toa resistance device 3 Considering now more in detail the apparatus abovereferred to, the control valve device |4 comprises a self-lappingportion 32, a suppression magnet valve portion 33, and a pipe bracket34.

The self-lapping portion 32 comprises a casing defining a chamber 35,and having a supply valve 36 `adapted when unseated to supply fluidunder pressure from the main reservoir 20 to the chamber 35, by way ofmain reservoir pipe 31, branch pipe 38, passage 39, the magnet valveportion 33, and passage 40;

The self-lapping portion is also provided with a movable abutment 4| inthe form of a piston containing interiorly thereof a release valve 42urged toward an unseated position by a spring 43. When the release valve42 is unseated, a communication is established between the chamber 35and the atmosphere, comprising passages 44, a chamber 45, and pipe andpassage 46.

The movable abutment 4| is subject on its lower side to pressure offluid in chamber 35 and on its upper side to pressure of a regulatingspring 41. Tension on the regulating spring may be regulated by anadjusting member 48. The degree of movement of the movable abutment 4|upward may be varied by a set screw 49, which is adaptedvto engage astem 56 associated with the movable abutment.

For seating the release valve 42 and for unseating the supply valve 36against opposition of its spring 5|, there is provided a mechanismcomprising a lever 54 pivotally mounted intermediate its ends at to aplunger 56. The plunger 56 is slidably disposed in a bore 51 and ismovable back and forth in this bore.

The left end of the lever 54 carries a stem 58 which is disposed in arecess in the supply valve 3'6. The right end of the lever 54 carries aroller 59 which is adapted to engage the stem of the release ,valve 42.

When the plunger 56 is actuated upwardly, the lever 54 fulcrums aboutits left end to first seat the release valve 42 against opposition ofits spring 43, and then fulcrums about its right end to unseat thesupply valve 36 against opposition of its spring 5|. It is to be hereunderstood that the release valve spring 43 is lighter than the suppl'yvalve spring 5|, whereas both springs 43 and 5| are much lighter thanthe regulating spring 41, so that during the aforedescribed movement ofthe plunger 56, the regulating spring 41 is unappreciably compressed.

When the release valve 42 is seated and the supply'valve 36 is unseated,fluid under pressure will flow to chamber 35. As the pressure in thischamber increases, it acts upon the movable abutment 4| to urge itupwardly against opposition of the regulating spring 41. This movementof. the movableabutment 4| permits the lever 54 to rotate about itsfulcrum 55 under action of the supply valve spring 5|, the limit ofrotation being reached when the supply valve 36 is seated. When thesupply valve 36 is seated, the supply of uid under pressure to thechamber 35 will be lapped.

Now the parts are so designed that the pressure at which the lap takesplace is dependent upon the degree o-f movementlofthe plunger 56upwardly.

If the pressure should exceed this value, then the movable abutment 4|will continue to move upwardly until the release valve 42 is unseated,whereupon fluid under pressure will be released from chamber 35, throughthe communication aforedescribed, until the pressure drops to thedesired value.

The chamber 35 is in communication with the brake cylinder I0 by way ofpipe and passage 6|, the double check valve device I5, and pipe 62, sothat variations of the pressure in chamber 35 determine the degree ofbrake cylinder pressure, and hence the degree of application of thefluid pressure brakes.

The plunger 56 is actuated upwardly by an arm 60 secured to a shaft 52which is rotated by a lever |36. The lever |30 is biased to a releaseposition by a spring 53, as shown.

The magnet valve portion 33 is embodied in a casing provided with avalve 63, which is urged toward an unseated position by a spring 64 andtoward a seated position by action of an electromagnet (not shown) inthe upper part of the casing which, when energized, actuatesthe valve 63downwardly. As will be observed, the'valve 63 controls the communicationfrom the main reservoir 20 to the seat of the supply valve 36, and solong as this valve is unseated this communication is open, and is closedwhen this valve is seated.

The'double check valve device |5 is embodied in a `casing comprising aslide valve 66, which moves to the left or right depending upon wheth-`er the pressure of the fluid supplied from pipe 6| or that from pipe 61is the greater.

The check valve device I6 is also embodied in a casing and is providedwith two valves 68 and 69 connected by a stem 1|) and disposed,respectively, in chambers` 12 and 13. The stem 1|] is slidable in afluted center wall 1|.

When the pressure of fluid supplied to chamber 12 exceeds the pressureof uid supplied to chamber 13, the valve 68 will seat while valve 69will be unseated. When the pressure supplied to chamber 13 exceeds thatsupplied to chamber 12, the valve 69 will seat while the valve 68 willunseat. It will thus be seen that with one or the other of the twovalves seated, fluid under pressure may ow past the unseated valvethrough pipe 61, double check valve I5, and pipe 62 to the brakecylinder I0.

The'derail throwing brake valve device l1 is embodied in a casing havinga chamber 15 in which is disposed a rotary valve 16 rotatable by ahandle 11 secured to a shaft 18 engagingwith the rotary valve. Therotary valve 16 is adapted to establish communication between a pipe 19and an exhaust port 80 by way of cavity 8|, when the handle 11 is inrelease position. When the handle 11 is in application position, thiscommunication is cut off and a communication is established between mainreservoir pipe 31 and the pipe 19, by a port 82 in the rotary valve 16,as is shown in Fig. '1.

The backing up valve device I8 is embodied in a casing having a rotaryvalve 85 adapted in application position to establish a communicationbetween the main reservoir pipe 31, by way of check valve device I9, anda second pipe 86 leading to the double check valve device I6. This valvedevice also has a lap position, in which this communication is closed,as is shown in Fig. 10. In its release position, the valve deviceconnects the pipe 86 to atmosphere by way of exhaust port 81, as shownin Fig. 9.

The check valve device |8 is a simple check valve device having a ballvalve 88 which permits flow of fluid under pressure from the mainreservoir 20 to the backing up valve device |8, but prevents now in theopposite direction. i

The magnetic track brake device H may be any of the types commonlyemployed for track braking purposes. This brake .device may be heldsuspended in its inoperative position above a track rail by the raisingcylinder 2|, which is embodied in a casing having a chamber 90 in whichis disposed a piston 9| connected to a yoke 92 attached to the brakedevice |I. When fluid under pressure is supplied to the chamber 90, thebrake device will be held in its inoperative position, and when fluidunder pressure is released from this chamber the brake device will dropby gravity to engagement with the rail.

The magnet valve device 22 is provided for controlling the supply offluid under pressure to and its release from the chamber 90. This magnetvalve device may comprise a double beat valve 93 urged toward an upperseated position by a spring 94, and toward a lower seated position byaction of an electromagnet in the upper part of the valve device casing,which when energized actuates the double beat valve 93 downwardly.

When the double beat valve 93 is in the upper seated position fluidunder pressure is supplied from the main reservoir 20, by way of pipes31 and 95, past the unseated double beat valve 93, and through pipe 96to chamber 90. When the double beat valve 93 is in lower seatedposition, this communication is cut off and fluid under pressure isreleased from the chamber 90 to the atmosphere past the open upper seatof the double beat valve,- and through exhaust -port 91. The thermalrelay 23 may be of any of the types which respond to a predeterminedtemperature to close contacts |00, as by a bridging contact member I0 I.For the purpose of illustration, I have shown a relay of the bimetallictype, comprising two thermal elements |02 exposed to the temperature ofa heating coil |03 connected across a resistance |04 in circuit with thetrack brake device When the temperature of the coil |03 is below apredetermined value the thermal elements |02 will position the bridgingcontact |0| as shown, but as the temperature of coil |03 approaches thepredetermined or critical value, bridging contact |0| will be actuatedtoward and at the critical temperature into engagement with thestationary contacts |00. It is to be here understood that the heatingcoil |03 is designed to have a temperature rise characteristiccorresponding to that of the exciting winding in the brake device sothat the functioning of the thermal relay 23 corresponds to temperatureconditions in the magnetic track brake device.

The controller mechanism 26 preferably comprises a drum |06 havingdisposed thereon and insulated therefrom separate contact segments |01,|03, |09 and ||0. These contact segments are arranged to engagerespective contact fingers to |23, as is diagrammatically indicated inFig. l.

'I'he drum |06 is rigidly disposed on a rshaft |25, the rotation ofwhich determines engagement between the contact segments and contactfingers above'referred to. The shaft |25 also carries a cam |26, whichis adapted to engage one end of a lever |21, which is pivotally mountedintermediate its ends at |28, andconnected at its other end through rod|29 to the lever |30 on the aforedescribed brake valve device |4. Thecam |26 is designed to progressively actuate lever |30 to the left asshaft |25 is rotated in a counterclockwise direction. l

Rotation of the shaft |25 is governed by the master control mechanism28. This mechanism is embodied in a casing having a chamber |32 to whichiiuid under pressure may be supplied upon unseating of a supply valve|33, which valve is normally urged toward unseated position. by spring|34. Operatively mounted in the casing is a movable abutment |35, whichcontains interiorly thereof a release valve |36,`urged toward anunseated position by a spring |31. When the release valve |36 isunseated a communication is established between the chamber |32 and theatmosphere, by way of passages |38, chamber |39, and exhaust .port |40.

The movable abutmentY has a stem |4| slidable in the casing of themechanism and connected by a link |42 to one end of a lever |43. 'I'helever |43 is pivotally mounted at |44 to a supporting structure |45,andhas its upper end connected to a cable |46 which extends overa pulley|41 and also over a second pulley |48 secured to the shaft |25. Thecablel |46 is connected at its other end to a spring |49v attached to abracket |50. The spring |49 is normally under sufficienttension'torotate the shaft 25 to its extreme clockwise position, asviewed in Fig. l.

When the supply valve |33 is unseated, fluid under pressure may flowfrom the main reservoir 20, through the main reservoir pipe 31, and

.plunger |55 slidably disposed in a bore |56. The

levers |53 are connected at their upper ends to a stem |51 whichprojects into a slot in the supply valve |33. At their lower ends thelevers |53 carry a roller v|56 which engages the stem of the releasevalve |36.

When the plunger |55 is actuated to the right, the levers |53 fulcrumabout their upper ends to seatthe release valve y|36 againstoppositionof. the spring |31, and then fulcrum about their lower ends to unseatthe supply valve |33 against opposition of its spring |34. It is to behere understood that therelease spring |31 is lighter than the supplyspring |34, to thereby permit the operation just described. When thesupply valve |33 is unseated, and fluid under pressure is supplied tothe chamber |32, the pressure of thisv fluid acts upon'the movableabutment |35 to urge it to the right. As the movable abutment moves tothe right it rotates the lever |43 in a counterclockwise direction, thuspulling cable |46 with it. This causes rotation cf the shaft |25 in'acounterclockwise direction, against opposition of spring |49.

As the movable abutment |35 moves to the right the spaced levers |53fulcrum about their pivot |54 and move in 'a counterclockwise directionunder action of the supply valve spring |34, until the supply valve |33is seated. When supply valve .|33 seats,- the supply of fluid underpressure to chamber |32 will be lapped, and the rotation ofshaft |25will cease. The parts are so designed that valve` |33 seats when thepressure in chamber `|32 corresponds to the degree of movement ofplunger |55. It will thus be apparent that the rotation of shaft |25 isgoverned by the degree of movement of the plunger |55 to the right.

For actuating'thevplunger |55 to the right there is provided a 'cam |60securedto a shaft |6| which, through suitable ttings |62, is rotatableby a handle |64.- The .parts are so designed that the plunger |55 isactuated to the right a degree corresponding to the degree of movementof the handle I 64 in an application zone, as depicted in Fig. 2. Thusit followsthat the degree of rotation 0f shaft |25 corresponds to thedegree of movement of the handle |64 in the application zone.

As shown in Fig.v 2, the handle |64 has a release position, a handle-olfposition, and is movable into an application zone. 'Ihe handle issodesigned that when in the release or any application position it cannotbe removed, but when moved to the handle-olf position a lug |65 comesadjacent a slot |66 to permit removing of the handle. .As will moreclearly appear later, the handle |64 `is used to also actuate the vbacking up valve device I8.

The control mechanism 20 also includes a rotary valve |68 which, in theposition shown in Fig. l, establishes acommunication from the pipe 19through passage |68, cavity |10, and passage I1I, with pipe |12 leadingto the aforementioned chamber 13 in the Ydouble check valvedevice I6.

The rotary valve |68 is movable to a position where this communicationis closed and the pipe |12 connected to the main reservoir pipe 31,through cavity |10 and passage |13, which passage contains a springloaded check valve |14 adapted to permit flow only from the mainreservoir to the pipe |12 and to prevent flow in the opposite direction.

The movement of the rotary valve |68 to establish the secondcommunication referred to is accomplished when the handle |64 is movedto the handle-off" position. When the handle |64 is thus moved, a cam|15 secured to the shaft I6I moves with the shaft to turn the linger|16, attached to the rotary valve |68, from the full line position shownin Fig. l to that indicated to the right thereof, for establishing thesecond mentioned communication. The function of the cam |15 in shiftingthe finger |16 is more clearly shown in Figs. 3 and 4.

The operation of this embodiment of my invention is as follows:

Running condition When the vehicle is to be operated under power, thebrake controller handle |64 is maintained in release position, in whichcase the parts of the equipment will be in the positions shown inFig. 1. It willbe noted that the contact segment |01 connects the twocontact fingers III and I|2, so that power may be supplied to thedriving motors by operation of the motor controller 24. This power issupplied from a trolley |61 through a circuit which includes conductor|11, contacts |01, III and ||2, conductor-|18, motor controller 24,conductor |19, the driving motors, and

ground connection |80. The motors are thus operated to propel thevehicle.

It will be noted from Fig. 1 that the backing up valve devicel I8establishes a communication between the main reservoir pipe 31 and pipe86 leading to the double check valve device I6, thus causing the valve68 therein to be seated and the valve 69 to be unseated. The one handle|64 is employed to operate the master control mechanism 28 as well asthe backing up valve device 8. When the handle |64 is removed from thebacking up valve device I8 it must be rotated to the service, handle-offposition, as indicated in Fig. 8, in which position the communication isestablished as shown in Fig. 1. The purpose of this will appear morefully later.

, Normal application When it is desired to effect a normal applica--tion of the brakes, the brake controller handle |64 is moved into theapplication zone toa degree according to the desired degree of braking.As the handle |64 is thus moved, the release valve |36 is seated and thesupply valve |33 is unseated, so that fluid under pressure is suppliedto the chamber |32. As before described, this Causes the movableabutment |35 to be actuated to the right to effect rotation of shaft |25to the same degree as manual movement of the handle |64. Assuming nowthat shaft |25 is rotated to a position corresponding to the degree ofmovement of handle |64, it will be observed from Fig. 1 and Fig. 6 thatthe brake valve device I4 will be rst actuated to supply fluid underpressure to the brake cylinder I0, and that the controller mechanism 26will be then correspondingly operated to effect rst an application ofthe dynamic brakes and then of both the dynamic and magnetic trackbrakes.

As the controller mechanism 26 is operated to application position, thecontact segment |01 disengages from the contact fingers I|I and ||2 toisolate the driving motors from the trolley |61. At the same time, thecontact segment |68 engages the two contact fingers I|3 and I|4 toconnect the driving motors in a dynamic braking circuit, Which circuitincludes conductoi SSI, the contact fingers |I3 and I I4 (or one or bothof contact lingers I|5 and IIS, depending upon the degree of rotation ofthe drum |06) conductor |82, resistance 3|, and conductor |83. It willbe apparent from the arrangement shown that connecting contact fingersII5 and |I6 serve to -cut out portions of a resistance |84, and that thelower the resistance in the dynamic braking circuit the greater will bethe degree of dynamic braking.

As current ows in the dynamic braking circuit the voltage drop acrossthe resistance 3| will energize relay 30 and cause it to close itscontacts |86. Closing of these contacts establishes a circuit from abattery I 81 to the suppression magnet valve devi-ce 33 in the brakevalve device I4. This circuit includes, beginning at battery |81,conductor |88, contacts |86,conductor |89, the magnet valve device 33and ground connection |90. This effects energization 0f the magnet valvedevice 33 and causes it to seat its double beat valve 63. Seating ofthis double beat valve closes communication between the main reservoirand the chamber 35, so that uid under pressure cannot be supplied to thebrake cylinder due to operation of the self-lapping portion 32 of thebrake valve device I4.

At the same time, if the controller mechanism 76;

26 has been rotated far enough so that contact segment |09 has engagedcontact lingers II'I and IIB the lowering magnet valve device 22 will beenergized, through a circuit which includes beginning at the batterylill, contacts ISI of relay 25, conductor |92, contacts |09, Ill and H8,conductor |93, the magnet valve device 22, and ground connection |90.The magnet valve device 22 will thus be energized to seat its doublebeat valve 93. Seating f this double beat valve cuts off the supply ofiiuid under pressure from the main reservoir 20 to the chamber 30 in theraising cylinder 2|, and vents this cylinder to the atmosphere by way ofexhaust port Sl. The track brake device I I will then fall to engagementwith the rail due to gravity.

At the same time contact linger |09 engages Contact ngers Ill and ||8 italso engages contact nger IIS to connect the track brake device II tothe battery I8? through contact finger IIS, resistance |95, conductori9", the resistance |04, conductor I3?, the brake device |I, and groundconnection |98. The brake device II will thus be energized and produce abraking effect on the rail.

It is to be here understood that while the track brake device II hasbeen shown as suspended 'above a track rail by fluid pressure means, it

may be also suspended on springs and be attracted to engagement with therail upon energization thereof, or held suspended above the rail byelectrical means which is deenergized or energized upon rotation of thecontroller mechanism 26, all of these means being commonly known andemployed in the art.

It will thus be seen that upon effecting a normal application of thebrakes the magnetic track rakes and dynamic brakes are applied While thefluid pressure brakes are held suppressed so long as the dynamic brakesare effective.

When the speed of the vehicle diminishes the effectiveness of thedynamic brakes will decrease at or near the end of the stop. When thiseiectiveness has decreased below a predetermined value, the relay 30will be deenergized and thus open its contacts |85. Opening of thesecontacts deenergizes the suppression magnet valve device 33, so that theiluid pressure brakes are then applied to insure that the vehicle bestopped and held at rest.

The magnetic track brakes will be effective throughout the lentire stop,but if these brakes are maintained energized after the vehicle comes toa stop they may be damaged due to overheating. At the time the magnetictrack brakes were applied contact segment IIil connected contact fingers|22 and |23. Connecting these fingers partially establishes a circuit tothe relay 25, which circuit includes beginning at battery |81, conductor|88, now opened contacts |00 of thermal relay 23, conductor 200, relay25, conductor 20|, contacts H0, |22 and |23, and ground connection 202.Since relay contacts |00 are opened, the relay 25 will not be energized.

When, however, the temperature of the heating coil |03 reaches apredetermined value, which will usually not be attained until after thevehicle has come to rest, the thermal relay will close its contacts |00so that relay 25 will be energized, thus opening contacts I9! andclosing contacts 203. Closing of contacts 203 forms a holding circuitfor the relay so that it will remain energized until the controllermechanism 25 has been actuated back to the position where the trackbrakes are normally released.

Opening of the contacts ISI interrupts the cir-` cuit to both the magnetvalve device 22 and the track brake device I I, so that the magnetictrack brake will be entirely released. It will thus be seen that thethermal relay 23 functions to release the magnetic track brakes at apredetermined temperature of the heating coil |03.

When it is desired to eiect a full release of the brakes, the brakecontroller handle 54 is returned to release position. In this positionthe supply valve |33 will be seated and the release valve |35l unseated,so that fluid under pressure is released from the chamber |32. Spring|49 will then return shaft |25 to its release position, in whichposition the vehicle motors will be disconnected from the dynamicbraking circuit, while the track brakes will likewise be disconnectedfrom the battery |31. 25 has in the meanwhile been energized byoperation of the thermal relay 23, the return of the controllermechanism 25 to release position interrupts the circuit through ngers|22 and |23 to the relay 25, and the relay thus drops to its lowermostposition.

Deraz'l throwing application When the vehicle approaches a derail and itis desired to close the derail so that the vehicle may pass, theoperator turns the handle 'Il of the derail throwing brake valve devicell to application position, as indicated in Fig. 7, while permitting thehandle |64 to remain in release position. Fluid under pressure is thensupplied from the main reservoir to pipe 19 from which it iiows throughpassage |59, cavity |10, passage IlI, pipe |12, past the unseated valve59 in the double check valve device I6, pipe l, past slide valve 66 indouble check valve device I5, which moves to the right, and through pipe62 to the brake cylinder I0. The iiuid pressure brakes only will then beapplied.

The purpose of providing the derail throwing brake valve device Il is topermit anapplication of the uid pressure brakes soas to hold the vehicleat rest while the operator moves the motor controller 24 to power supplyposition, to cause current to pass through an electromagnet in thederail throwing switch to close the derail. This could not beaccomplished by movement of the main brake controller handle |54, as themotors would then be disconnected from the trolley and current could notbe caused tol ow through the electromagnet n the derail throwing switch.

After the derail throwing switch has been closed the handle 'I4 isreturned to release position to release the uid pressure brakes. kThevehicle may then proceed on past the derail switch.

Backing-ap application When it is desired to back the vehicle up, the`operator turns the main brakecontroller handle I 64 to handle-offposition, in which position ythe handlecan be removed and then taken tothe rear of the car to operate the backing up valve device I8.

When the handle |64 is thrown to the handleoi position on the main brakecontroller 28, the rotary valve |68 is moved to the position wherecommunication between the passages |63 and I'II is interrupted and acommunication, formed between passages I'II and |13, to apply the iluidpressure brakes. Thus when the handle- |64 is taken to the rear of thecar'and attached to the backing up brake valve device I8 the brakes areapplied, and the backing up valve device I8 In case the relay v rsi4must be then operated to establish the communication as shown in Fig. 9in order to release this application.

Thereafter, applications may be made by operating the brake valve deviceto the application position shown in Fig. l. To lap the brakeapplication the brake valve device is operated to the position shown inFig. 10.` When it is desired to again operate the vehicle from the frontend the handle |64, now on the backing up valve device I8, is turned tothe service, handle-olf position, as shown in Fig. 81, in which positionit may be removed and then taken to the front end of the car.

While I have described my invention with particular reference to oneembodiment thereof, it is to be understood that it is not my intentionto be limited to the specific arrangement shown for this embodiment, orotherwise than by the spirit and scope of the app'ended claims.

Having now described my invention, what I claim as new and desire tosecure by Letters Patent, is:

l. In a vehicle brake system, in combination, electric braking means,uid pressure braking means, common control means including a controlvalve device and an electric brake controller mechanicallyinterconnected and operable to various application positions to effectand control applications of said two braking means, fluid pressureoperated means for operating said common control means, a controlelement movable to `different positions, and means for effecting asupply of uid under pressure to said fluid pressure operated meansaccording to the degree or extent of movement of said control element.

2. In a vehicle brake system, in combination, electric brake means,fluid pressure brake means, common control means including a controlvalve device and an electric brake controller` mechanicallyinterconnected and operable to various application positions to effectand control applications of said two brake means, a control handlemovable to different positions, and fluid pressure means for actuatingsaid common control means to an application position corresponding tothe position of said control handle.

3. In a vehicle brake system, in combination, a plurality of brakesystems, common control means for controlling applications of saidplurality of brake systems, a mechanism having a chamber and a supplyvalve operable when open to effect a supply of fluid under pressure tosaid cham-ber, manually operated means for effecting opening of saidsupply valve, and a movable abutment subject to the pressure of fluid insaid chamber and operated by said pressure to operate said controlmechanism and to control closing of said supply valve.

4. In a vehicle brake system, in combination, a plurality of brakesystems, common control means for'controlling applications of saidplurality of brake systems, a control mechanism comprising a casinghaving a chamber and a supply Valve operable when open to effect asupply of fluid under pressure to said chamber, a movable abutmentsubject to the pressure in said chamber and movable according to thedegree of pressure established in said chamber, means connecting saidabutment to said common control means and actuating said common controlmeans as said abutment moves under inuence of the pressure in saidchamber, and means for closing said supply valve upon a predeterminedmovement of said abutment.

5. In a vehicle brake system, in combination, fluid pressure brakemeans, electric brake means, common control means including a controlvalve device and an electric brake controller mechanicallyinterconnected and for controlling applications of said two brake means,a casing having a chamber, a valve operable manually tol effect a supplyof fluid under pressure to said chamber, a movable abutment subject tothe pressure of fluid supplied to said chamber and operable at apreselected pressure to eiect closing of said valve, and means operablein accordance with operation of said abutment for actuating said commoncontrol means.

6. In a vehicle brake system, in combination,

a brake cylinder, a magnetic track brake device, veehicle driving motorsadapted to be operated as dynamic brakes, common control means operableto effect a supply of fluid under pressure to ,v

fluid supplied to said chamber for effecting seating of said supplyvalve when the pressure in said chamber corresponds to the degree ofmovement of said handle, and means governed by the movement of saidabutment for correspondingly actuating said common control means.

7. In a vehicle brake system, in combination, magnetic track br-akemeans, control means operable to an application position to effect anapplication of said track brake means, thermal means operable at apredetermined temperature to effect a release of said track brake means,and means for causing said predetermined temperature to correspond totemperature conditions in the braking portion of said track brake means.

8. In a vehicle brake system, in combination, magnetic track brakemeans, means for effecting an application of said track brake means, athermal relay operable at a preselected temperature to actuate a set ofcontacts, means responsive to actuation of said contacts for effecting arelease of said track brake means, and means for causing saidpreselected temperature to correspond to the temperature conditionswithin energizing portions of said track brake means.

9. In a vehicle brake system, in combination, magnetic track brake meanshaving an energizing Winding, means for establishing a circuit throughwhich current is supplied to said winding to effect energization thereofto produce a braking effect, means for producing a heating effectsimulating the heating conditions within said Winding when energized,and thermal means responsive to said heating eiect for controlling theduration of energization of said winding.

10. In a vehicle brake system, in combination, magnetic track brakemeans, means for establishing a circuit through which current issupplied to eifect energization of said magnetic track brake means,means connected to said circuit for producing a heating effectcorresponding to the heating effect within said brake means, and thermalmeans responsive to a predetermined temperature of the heating effectproduced by said last mentioned means for effecting deenergization ofsaid track brake means.

11. In a vehicle brake system, in combination,

magnetic track brake means, means for establishing a circuit throughwhich current is supplied to energize said magnetic track brake means,means responsive to the current in said circuit for producing a heatingeffect corresponding to the heating effect within said brake means, andmeans responsive to a predetermined temperature of said heating effectfor effecting opening of said circuit.

' 12. In a vehicle brake system, in combination, magnetic track brakemeans, means for establishing a circuit through Which current issupplied to energize said magnetic track brake means, means connected tosaid circuit for producing a heating effect, normally open contacts,means responsive to closing of said contacts for effecting opening ofsaid circuit, and means operated at a predetermined temperature of saidheating effect for closing said contacts.

13. In a vehicle brake system, in combination,

magnetic track brake means, a controller device YWhich current issupplied When said controller device is operated to supply current tosaid track brake means, a thermal relay operated at a predeterminedtemperature of said heating coil, and

means responsive to operation of said thermal relayv for effectingdeenergization of said track brake means.

14. In a vehicle brake system, in combination, a magnetic track brakedevice, a controller device operable to application position to effectenergization of said track brake device, a heating coil adapted to havecurrent supplied thereto when said track brake device is energized, thetemperature riseof said heating coil corresponding substantially to thetemperature rise of said track brake device when current is supplied toboth, a thermal relay responsive to the temperature of said heating coiland adapted to actuate contacts at a predetermined temperature of saidcoil, and means responsive to actuation of said contactsA for effectingdeenergization of both said heating coil and said magnetic track brakedevice.

15.A In a vehicle brake system, in combination, a magnetic trackV brakedevice, a circuit adapted tozbe established at Will to supply current tosaid magnetic track brake device, a resistance in said circuit, aheating coil connected Vacross said resistance, athermal relay havingcontacts adapted to be actuated ata predetermined temperature of saidheating coil, and means responsive to actuation of said contacts foreffecting opening of said circuit.

16. In a vehicle brake system, in combination, a magnetic track brakedevice, means for establishing at will a circuit through which currentis supplied to energize said track brake device, a heating coilconnected to said circuit and adapted to have temperatures producedtherein corresponding to those produced in said track brake device,normally open contacts, thermal means for closing said contacts at apredetermined temperature of said heating coil, and means responsive toclosing of said contacts for effecting opening of said circuit.

1'7. In a vehicle brake system, in combination, fluid pressure brakemeans, an electric brake means, common control means operable tocondition each of said brake means for application, manually operatedbrake control means operable in a release position to establish acommunication through which fluid under pressure may be supplied toeffect an application of said fluid pres'- sure brake means only, andoperable to'an application position to actuate said common controlmeans, and independent manually operated means for effecting a supply offluid under pressure through said communication when said firstmentioned manually operated means is in release position. ,Y

18. `In a vehicle brake system, in combination, a plurality of brakesystems, common control means for controlling applications of saidplurality of brake systems, manually operated means operable in releaseposition to establish a communication through which fluid under pressuremay be supplied to effect an application of one of said brake systems,and operable to application position to close said communication and toactuate said common control means, and independent v means for effectinga supply of fluid under pressure to said communication when saidmanually operated means is in release position.

19. In a vehicle brake system, in combination, brake means, a manuallyoperated controlv means for the head end of the vehicle for controllingapplications of said brake means, said manually operated control ymeansestablishing in its release position a communication throughwhich fluidunder pressure may be supplied to effect an application of vsaid brakemeans independently of p operation of saidmanually operated means, and

being operable to a handle-off, a release and an application position, avalve device for the rear end of the vehicle for also effecting anapplication of said brake means, and a common control handle foractuating said v manually operated means and said valve device, saidcommon'handle being removable from said manually operated means only inthe lhandle-off position, said manually operated means closing saidcommunication When operated to said handle-off position.

20. In a vehicle brake system, in combination, magnetic track brakemeans, dynamic brake means, means operable to effect an application ofboth of said brake means, and operable t0 effect arelease of both ofsaid brake means, and I thermal means for independently effecting arelease of said magnetic track brake means before said last mentionedmeans has been operated to effect the release of both of said brakemeans.

21. In a vehicle brake system,'in combination, magnetic track brakemeans, dynamic brake means, a controller mechanism operable to anapplication position to simultaneously effect an application of both ofsaid brake means, and thermal means rendered operative only when saidcontroller mechanism is in application position for controlling theduration of application of said magnetic track brake means.

22. `In a vehicle brake system, in combination, magnetic track brakemeans, dynamic brake means, a controller device'operable to applicationposition to effect an application of both of said brake means, a circuitadapted to be closed to effect a release of said magnetic track brakemeans, normally opened contacts in said circuit, thermal means forclosing said contacts, and means for preventing complete closure of saidcircuit until said controller device has been operated to apredetermined application'position.

23. In a magnetic track brake system having coil energized brakes,temperature responsive means for preventing the generation of excessiveheat in the brake coils by interrupting the coil energizing circuit.

24. In a magnetic track brake system includ- -ing a brake shoe having acoil and an energizing circuit therefor, a shunt in. said circuit, arelay adapted to be o-perated thereby, and a power switch operated bysaid relay, said relay being adapted, upon iiow of current ofpredetermined value, to cause said power switch to open after apredetermined interval, whereby to arrest the energization of said brakeshoe coil and prevent overheating thereof.

25. In a magnetic track brake system including a brake shoe having acoil and an energizing. circuit therefor and means in said circuitadapted to limit the time of energization of the brake coil whereby toprevent overheating of said coil, said means comprising a shunt, a relayadapted to be energized by said shunt and upon energization, to operate,after a lapse of time, to cause a power switch to open, said powerswitch, upon energization, being adapted to interrupt said energizingcircuit and prevent overheating of said brake shoe coil.

26. In a mechanism for arresting the energization of a magnetic trackbrake coil by interruptving the energizing circuit thereof, a shuntcon-v nected in said energizing circuit, a relay adapted to be energizedby said shunt, and means adapted to be made operable upon energizationof said relay to interrupt the energizing circuit of the track brakecoil. Y 27. In a magnetic track brake system including a brake shoehaving a coil and yan energizing circuit therefor, a power switchadapted when energized to interrupt said energizing circuit, and meansfor energizing said power switch including a shunt adapted upon the flowtherethrough of current of predetermined value to cause energization ofsaid power switch to open said brake shoe energizing circuit after apredetermined interval. 28. In a magnetic track brake system including abrake shoe having a core, a coil, and an energizing circuit therefor;switch means in said circuit, solenoid means for operating said switchmeans to open and close said circuit, and means operative substantiallyin accordance with the temperature of said coil adapted to cause saidsolenoid means to open said switch means when a predeterminedtemperature of the coil is reached. 29. In a magnetic track brake systemincluding a brake shoehaving a core, a coil, and an energizing circuittherefor; switch means in said circuit, solenoid means for operatingsaid switch lmeans to open and close said circuit, relay means foroperating said solenoid means, and means operative substantially inaccordance with the temperature of said brake shoe coil adapted, when apredetermined temperature is reached, to cause said relay means tooperate said solenoid means to open said switch means and arrest theenergization of the coil whereby to prevent the production of excessivetemperature in said coil.

30. In a magnetic track brake system including a brake shoe having acore, a coil, and an energizing circuit therefor; switch means in saidbrake coil energizing circuit, an energizing circuit for said switchmeans, and temperature responsive switch means associated with saidbrake shoe connected in said switch energizing circuit and operativesubstantially in accordance with the temperature in said brake shoecoil, said temperature responsive switch means being adapted, when saidtemperature exceeds a predetermined value, to cause said switch means toopen said energizing circuit. l y f 3l. In a magnetic track brake systemincluding a brake shoe having a core, a coil, and an energizing circuittherefor; normally closed ,switch means in said circuit, solenoidmeans-for opening said switch, and means operative substantially inaccordance with the temperature in said brake shoe coil for energizingsaid solenoid means to cause said switch means to be opened thereby.

32. In a magnetic track brake system including a brake shoe having acore, a coil, and an energizing circuit therefor; normally opentemperature responsive circuit switch means associated with said brakeshoe adapted to close substantialf ly when the temperature inV said coilexceeds a predetermined amount, a circuit operatively connected to saidtemperature responsive circuit switch means and having ytherein asolenoid coil, and means including ak relay switch responsive to theenergization of said solenoid coil for causing interruption of the brakecoil energizing circuit when said solenoid coil is energized byvclosingof said temperature responsive circuit switch means.

33. In a vehicle brake system, in combination, magnetic track brakemeans, control means operable to an application position to eiiect anapplication of the track brake means, andthermal means operable at apredetermined temperature to effect a release of said track brake means.

34. In a magnetic track brake system having coil energized brakes,temperature responsive means forinterrupting the coil energizingcircuitv

